Spillover effects of structure-adjustment pollution reduction measures in China's iron and steel industry.

The iron and steel industry (ISI) is a significant source of sulfur dioxide and particulate matter pollution in China. Existing research on regional environmental regulation or ISI emission reduction strategies tends to overlook spillover effects and the enterprise perspective. During the heating season, production limitations in ISI are potential policy measures for achieving structural emission reductions in heavily polluted cities in China's Jing-Jin-Ji and surrounding regions. We adopt a bottom-up modeling approach, incorporating effective production time to describe enterprise behavior and establishing a quantitative trade model based on trade theory. By modeling three types of production restriction policies outlined in policy documents, we evaluate the emission reduction effects of structure-adjustment measures using the example of reduced effective production time for steel-producing enterprises in the air pollution transmission channel in the Beijing-Tianjin-Hebei area. The results indicate the following: (1) Reducing the effective production time of ISI enterprises can help decrease domestic production value and total factor productivity in pollution-intensive industries, including but not limited to ISI. It also leads to reduced emissions of various pollutants in the implementation regions. (2) Due to interprovincial trade and input-output linkages, structural reduction measures in certain regions have implications for almost all other provinces' industrial structures. Differences in initial industrial structures, factor endowments, and geographical locations contribute to varying directions and magnitudes of industrial structural changes. Pollution-intensive industries' share tends to increase higher in less developed regions. (3) Our estimated pollution reduction is smaller compared to the literature evaluating clean air policies in similar regions using top-down strategies. This discrepancy arises because we analyze a single policy tool rather than modeling industry-wide emission fluctuations from the top down. Additionally, our modeling approach allows us to examine dynamic changes in comparative advantages. The increase in production scale for certain industries in policy-affected regions partially offsets the decline in pollution emissions. These findings enhance our understanding of structure-adjustment reduction measures' role and highlight their potential advantages and limitations.

A Facility-Level Phaseout Strategy for China's Blast Furnaces to Address Multiple Policy Objectives.

Given the urgency of addressing climate change and the declining demand for steel, it is imperative that China's iron and steel industry begin phasing out its primary production facility, the blast furnace. While there are various studies examining the decarbonization pathways for this sector and the resulting impacts, research exploring how to design decarbonization pathways that consider economic, environmental, and regional aspects equally is lacking. Moreover, it remains unclear how the individual heterogeneity of facilities affects the effectiveness of climate policies. In this study, we address the aforementioned research gaps by proposing a novel strategy that takes into account economic, carbon, water, and health factors in determining the priority for the closure of China's blast furnaces. We developed a bottom-up framework that incorporates a facility-level data set, a stock-driven dynamic material analysis, and retirement metrics with uncertain parameters to measure the multidimensional impacts of various phaseout pathways for China's blast furnaces. We have identified potential pathways that can improve environmental efficiency in multiple aspects compared with the cost-minimization pathway without impeding regional equality.

Iron and Steel Industry Emissions: A Global Analysis of Trends and Drivers.

The iron and steel industry (ISI) is important for socio-economic progress but emits greenhouse gases and air pollutants detrimental to climate and human health. Understanding its historical emission trends and drivers is crucial for future warming and pollution interventions. Here, we offer an exhaustive analysis of global ISI emissions over the past 60 years, forecasting up to 2050. We evaluate emissions of carbon dioxide and conventional and unconventional air pollutants, including heavy metals and polychlorinated dibenzodioxins and dibenzofurans. Based on this newly established inventory, we dissect the determinants of past emission trends and future trajectories. Results show varied trends for different pollutants. Specifically, PM2.5 emissions decreased consistently during the period 1970 to 2000, attributed to adoption of advanced production technologies. Conversely, NOx and SO2 began declining recently due to stringent controls in major contributors such as China, a trend expected to persist. Currently, end-of-pipe abatement technologies are key to PM2.5 reduction, whereas process modifications are central to CO2 mitigation. Projections suggest that by 2050, developing nations (excluding China) will contribute 52-54% of global ISI PM2.5 emissions, a rise from 29% in 2019. Long-term emission curtailment will necessitate the innovation and widespread adoption of new production and abatement technologies in emerging economies worldwide.

Identification of priority pollutants at an integrated iron and steel facility based on environmental and health impacts in the Yangtze River Delta region, China.

Emissions from the iron and steel industry are a major source of air pollution. To investigate the composition characteristics, estimate the secondary transformation potential, and assess the ecological risk and human health risks of air pollutants from iron and steel industry, field measurements of volatile organic compounds (VOCs) and trace metals (TMs) were conducted simultaneously from 2020 to 2022 in the Yangtze River Delta (YRD) region, China. The average mixing concentration of VOCs (Σ64VOCs) was 58.2 ppbv. Alkanes, alkenes and aromatics were the major components. Benzene and ethylene were the most abundant VOC species. In the O3 season, the calculated OH loss rates (LOH) and ozone formation potential (OFP) were 10.87 S-1 and 181.74 ppbv, respectively, which increased 39.54% and 21.51% compared to the non-O3 season. Furthermore, the O3-VOCs-NOx sensitivity indicated that O3 formation was under the VOCs-limited regime. The average concentration of total 10 trace metals (Σ10TMs) was 226.8 ng m-3, Zn, Pb and Mn were the top abundant TM species. The results also found that Se was extremely contaminated; Pb and Zn was heavily to extremely contaminated; Cu, As and Ni were moderately to heavily contaminated. For lifetime cancer risk, the cumulative carcinogenic risks were 1.84E-5 for children, 6.14E-5 for adults and 1.83E-5 for workers. The carcinogenic risks of individual chemicals cannot be ignored, especially for Cr, Ni, benzene and 1,3-butadiene. The hazard index values for workers and residents were 0.53 and 2.23, respectively, suggesting a high non-carcinogenic risks to the exposed population. These findings deepen the understanding of the pollutant character of the iron and steel industry, and provide theoretical support for policy development on O3 pollution treatment and human health in the YRD region, China. For the study area, we recommend utilizing high-quality raw coal, reducing the volatile hydrocarbon content in the sinter feed, and installing absorption device for highly reactive VOC components at the exhaust outlet.

Multi-process and multi-pollutant control technology for ultra-low emissions in the iron and steel industry.

The iron and steel industry is not only an important foundation of the national economy, but also the largest source of industrial air pollution. Due to the current status of emissions in the iron and steel industry, ultra-low pollutant emission control technology has been researched and developed. Liquid-phase proportion control technology has been developed for magnesian fluxed pellets, and a blast furnace smelting demonstration project has been established to use a high proportion of fluxed pellets (80%) for the first time in China to realize source emission reduction of SO2 and NOx. Based on the characteristics of high NOx concentrations and the coexistence of multiple pollutants in coke oven flue gas, low-NOx combustion coupled with multi-pollutant cooperative control technology with activated carbon was developed to achieve efficient removal of multiple pollutants and resource utilization of sulfur. Based on the characteristics of co-existing multiple pollutants in pellet flue gas, selective non-catalytic reduction (SNCR) coupled with ozone oxidation and spray drying adsorption (SDA) was developed, which significantly reduces the operating cost of the system. In the light of the high humidity and high alkalinity in flue gas, filter materials with high humidity resistance and corrosion resistance were manufactured, and an integrated pre-charged bag dust collector device was developed, which realized ultra-low emission of fine particles and reduced filtration resistance and energy consumption in the system. Through source emission reduction, process control and end-treatment technologies, five demonstration projects were built, providing a full set of technical solutions for ultra-low emissions of dust, SO2, NOx, SO3, mercury and other pollutants, and offering technical support for the green development of the iron and steel industry.

The changes in spatial layout of steel industry in China and associated pollutant emissions: A case of SO2.

The spatial layout of the steel industry has an impact on the regional atmospheric environment. In this study, the steel industry evolution model and the driving force analysis model were combined to analyze the evolution of spatial layout of the steel industry in China and the driving factors of this evolution. In addition, the WRF-SMOKE-CMAQ model was used to analyze the spatial dynamics of SO2 emissions from the steel industry. Our analysis presents the evolution of the steel industry in China in four stages: policy-determining, resource-oriented, economic promotion and market-oriented stage. The change in the spatial layout of the Chinese steel industry resulted in a continuously decreasing trend of pollutants in temporal characteristics and a decreasing share of emissions in North China and a continuous growth in East China in spatial characteristics. Our simulation shows that, by 2025, the pollutant SO2 emission concentration will migrate to the southeast, subject to market-oriented factors.

Industrial-environmental management in China's iron and steel industry under multiple objectives and uncertainties.

Industrial-environmental management is a multi-objective optimization problem plagued with multiple uncertainties. Most studies only optimize few objectives and often neglect these uncertainties. This study builds a 6-objective optimization problem to quantify energy conservation and emission reduction (ECER) potentials in China's iron and steel industry. First, uncertainties are simulated through 100,000-time random sampling, NSGA-II and the mean-effective objective mechanism are applied to calculate optimal solutions. Finally, a global sensitivity analysis is performed to classify uncertainty parameters based on their impacts on objectives' performance. Results show: (1) There exist significant discrepancies between objectives' performance under certainty and uncertainty. For example, the deterministic CO2 intensity is 1148 kg/t, which is 11.93% lower than its value under uncertainty. Therefore, neglecting uncertainty increases the risk of noncompliance with policy targets as they might be too strict; (2) Two critical uncertainty parameters (steel ratios and technology penetration rates) have the most severe impacts on objectives' performance, hence, reducing their fluctuation can minimize uncertainties when estimating ECER potentials; (3) By-product recycling and energy efficiency measures have good performance in all objectives, thus, should be prioritized. Moreover, from 77-strategies assessed, 11 are identified as key-strategies due to their large ECER effects, hence, should be strongly promoted.

Technology innovation system analysis of decarbonisation options in the EU steel industry.

Decarbonisation of the iron and steel (I&S) industry is crucial in the efforts to meet the EU GHG emission reduction objectives in 2030 … 2050. Promoting decarbonisation in this sector will necessarily require the identification, development, and diffusion of breakthrough technologies for I&S production. This paper uses an approach inspired by the Technology Innovation System (TIS) to analyse the development of technology in the EU I&S industry and identify potential avenues of its decarbonisation. We have described key elements of the TIS, analyse the functioning of these elements and their interactions in a more general context of innovation dynamics and policy design; The focus has been put on the role of actors and the identification of the main specific blocking and inducement mechanism in the TIS to better explain its functioning. Risks and uncertainties have also been discussed. We argue that deep decarbonisation in the I&S industry is feasible but its TIS requires firm support, mostly political, to finance intensive R&D and reduce the business risk. To this end, all actors shall support more effectively the invention and implementation of new radical production technologies. The recommendations are mostly addressed to politicians although stressing the importance of collaboration of all actors.

Quantitative analysis of the precise energy conservation and emission reduction path in China's iron and steel industry.

A precise energy conservation and emission reduction (ECER) path in industrial sector contains two aspects: applying effective ECER measures and focusing on processes with significant ECER potential. However, most studies have investigated the ECER effects of an individual measure or only evaluated industrial-level ECER potential. Therefore, the objective of this study is to find a precise ECER path in China's iron and steel industry through quantitative analysis methods. First, this article adopts scenario analysis to simulate situations where different ECER measures are adopted and designs calculation methods to quantitatively evaluate the ECER effects in each scenario in 2020 and 2025. Second, through analysis of the application of ECER measures to certain processes, we calculate the ECER potential of different individual processes in the iron and steel industry. In addition, the conservation supply curve method and the quadrant method are used to measure the level of advanced technology application. The results show that: (1) for four types of ECER measures, the limitation of production output measure is most effective, contributing to 6.98% and 12.50% decreases in total industrial energy consumption and pollutant emissions in 2020 and 2025; moreover, the contribution of the adjustment of scale structure measure is comparatively low. (2) The sintering and ironmaking processes have strong ECER potential in 2020, while the steel making process also has high ECER potential in 2025. (3) 21 technologies are divided into 4 quadrants based on energy, popularity, and economic performance. In addition, we provide some suggestions for future ECER policies. In sum, this article provides an in-depth example of determining a precise ECER path in an important industry.

Environmental impact assessment of wastewater discharge with multi-pollutants from iron and steel industry.

The iron and steel industry discharges large quantities of wastewater. The environmental impact of the wastewater is traditionally assessed from the quantitative aspect. However, the water quality of discharged wastewater plays a more significant role in damaging the natural environment. Moreover, comprehensive assessment of multi-pollutants in wastewater from both quality and quantity is still a gap. In this work, a total environmental impact score (TEIS) is defined to assess the environmental impact of wastewater discharge, by considering the volume of wastewater and the quality of main processes. To implement the comprehensively qualitative and quantitative assessment, a field monitoring and measurement of wastewater discharge volume and the quality is conducted to acquire pH, suspend solids (SS), chemical oxygen demand (COD), total nitrogen (TN), total iron (TFe), and hexavalent chromium (Cr(VI)). The sequence of TEIS values is obtained as steelmaking > ironmaking > sintering > hot rolling > coking > cold rolling and TN > COD > SS > pH > Cr(VI) > TFe. The TEIS of the investigated steel plant is 26.27. The leading process lies in steelmaking with a TEIS of 19.98. The dominant pollutant is TN with a TEIS of 15.00. Finally, a sensitivity analysis is performed to validate the feasibility and generalisability of the TEIS.

Uncertainty analysis of industrial energy conservation management in China's iron and steel industry.

There are remarkable uncertainty factors in the industrial sector that enhance the difficulties of setting energy conservation strategies, such as the macro economy, industrial structures, and technical uncertainties. However, current studies simply predict the possible trends or conduct scenario analyses, and neglect uncertainty factors in the management of industrial energy conservation. In response, this article considers China's iron and steel industry as an example and builds the Industrial Energy Conservation Uncertainty Analysis (IECUA) model to recognize and analyze the uncertainty factors via a 200-thousand-time Latin hypercube sampling. Then, we propose some management measures, including setting energy conservation targets and energy conservation strategies. The results show that energy conservation targets should be more flexible than just the predicted values, to enhance the feasibility of their realization. In addition, energy conservation strategies are set at industrial and technique levels. On the one hand, such key parameters as production output, the coke/steel ratio, and pig iron/steel ratio, should be strictly controlled to avoid non-compliance risks. On the other hand, energy conservation technologies can be considered under four quadrants depending on their sensitivity to energy conservation and economic efficiency. Finally, some differentiated technologies promotion suggestions are made, such as economic stimulation, market entry standards and technical application guidelines.

Life cycle assessment and water footprint evaluation of crude steel production: A case study in China.

China, as the world's largest crude steel producer, is suffering from water scarcity and pollution. However, only a few systematic analyses on the environmental burdens and improvements of China's crude steel production have been conducted. Therefore, it is important for research to be done how China's steel industry can be improved in environment management. To help decision-makers understand this, a life cycle water footprint analysis including gray and blue water was performed based on the methodology prescribed in the ISO 14046 standard. A life cycle assessment was also conducted to improve the environmental performance of the steel industry. Results of these assessments revealed that gray water footprint, which is mainly derived from aquatic eutrophication, carcinogens, and non-carcinogens, is higher than blue water footprint. Optimizing indirect processes, including iron ore mining, magnesium oxide production, transportation, and electricity generation, played dominant roles in the reduction of gray water footprint. Furthermore, COD, Cr (VI), phosphate, BOD5, Hg, As, nitrogen oxides, particulates, and sulfur dioxide were the key substances for environmental improvements. The underestimation of direct water footprint showed the importance and urgency of implementing scientific and adequate monitoring indicators. Meanwhile, the environmental burden can be reduced by adopting a reasonable location of the steel industry on the basis of regional water resources and actual transportation status, improving the efficiency of raw material consumption, and optimizing the power structure.

Low-carbon transition of iron and steel industry in China: carbon intensity, economic growth and policy intervention.

As the biggest iron and steel producer in the world and one of the highest CO2 emission sectors, China's iron and steel industry is undergoing a low-carbon transition accompanied by remarkable technological progress and investment adjustment, in response to the macroeconomic climate and policy intervention. Many drivers of the CO2 emissions of the iron and steel industry have been explored, but the relationships between CO2 abatement, investment and technological expenditure, and their connections with the economic growth and governmental policies in China, have not been conjointly and empirically examined. We proposed a concise conceptual model and an econometric model to investigate this crucial question. The results of regression, Granger causality test and impulse response analysis indicated that technological expenditure can significantly reduce CO2 emissions, and that investment expansion showed a negative impact on CO2 emission reduction. It was also argued with empirical evidence that a good economic situation favored CO2 abatement in China's iron and steel industry, while achieving CO2 emission reduction in this industrial sector did not necessarily threaten economic growth. This shed light on the dispute over balancing emission cutting and economic growth. Regarding the policy aspects, the year 2000 was found to be an important turning point for policy evolution and the development of the iron and steel industry in China. The subsequent command and control policies had a significant, positive effect on CO2 abatement.

Analysis of the synergistic benefits of typical technologies for pollution reduction and carbon reduction in the iron and steel industry in the Beijing-Tianjin-Hebei region.

With its high energy consumption and pollutant emissions, the iron and steel industry is a significant source of air pollution and carbon emissions in the Beijing-Tianjin-Hebei (BTH) region. To improve air quality and reduce greenhouse gas emissions, a series of policies involving ultra-low emission, synergistic reduction of pollution, and carbon application have been implemented in the region. This study has assessed air pollutant and CO2 emission patterns in the iron and steel industry of the region by employing co-control effects coordinate system, marginal abatement cost curve, and numerical modeling, along with the synergistic benefits of typical technologies. The results have demonstrated that: (1) the intensive production activities pertinent to iron and steel enterprises has contributed greatly to the emission in Tangshan and Handan, where the sintering process is the main source of SO2, NOx, PM2.5, and CO, accounting for 64.86%, 55.15%, 29.98%, and 46.43% of the total emissions, respectively. (2) Among the typical pollution control and reduction measures, industrial restructuring and adjustment of the energy-resource structure have led to the greatest effects on emission reduction. Technologies exhibiting great potential in emission reduction and high-cost efficiency such as Blast Furnace Top Gas Recovery Turbine Unit (TRT) need to be promoted. (3) In Tangshan city with the highest level of steel production, the iron and steel production activities contributed to the concentration of 30.51% of PM2.5, 50.67% of SO2, and 42.54% of NO2 during the non-heating period. During the heating period, pollutants pertinent to the combustion of fossil energy for heating have increased, while iron and steel induced emissions have decreased to 23.7%, 34.32%, and 29.13%, respectively. By 2030, it is speculated that the contribution of the iron and steel industry to air quality will be significantly decreased as result of successful implementation of ultra-low emission policies and typical synergistic reduction technologies.

Quantifying China's iron and steel industry's CO2 emissions and environmental health burdens: A pathway to sustainable transformation.

Assessing the iron and steel industry's (ISI) impact on climate change and environmental health is vital, particularly in China, where this sector significantly influences air quality and CO2 emissions. There is a lack of comprehensive analyses that consider the environmental and health burdens of manufacturing processes for ISI enterprises. Here, we present an integrated emission inventory that encompasses air pollutants and CO2 emissions from 811 ISI enterprises and five key manufacturing processes in 2020. Our analysis shows that sintering is the primary source of air pollution in the ISI. It contributes 71% of SO2, 73% of NO x , and 54% of PM2.5 emissions. On the other hand, 81% of total CO2 emissions come from blast furnaces. Significantly, the contributions of ISI have resulted in an increase of 3.6 µg m-3 in national population-weighted PM2.5 concentration, causing approximately 59,035 premature deaths in 2020. Emissions from Hebei, Jiangsu, Shandong, Shanxi, and Inner Mongolia provinces contributed to 48% of PM2.5-related deaths in China. Moreover, the transportation of air pollutants across provincial borders highlights a concerning trend of environmental health inequality. Based on the research findings, it is crucial for ISI manufacturers to prioritize the removal of outdated production capacities and adopt energy-efficient and advanced techniques, along with ultra-low emission technologies. This is particularly important for those manufacturers with substantial environmental footprints. These transformative actions are essential in mitigating the environmental and health impacts in the affected regions.

Decomposition of the site-level energy consumption and carbon dioxide emissions of the iron and steel industry.

Identifying the key factors influencing energy consumption and CO2 emissions is necessary for developing effective energy conservation and emission mitigation policies. Previous studies have focused mainly on decomposing changes in energy consumption and CO2 emissions at the national, regional, or sectoral levels, while the perspective of site-level decomposition has been neglected. To narrow this gap in research, a site-level decomposition of energy- and carbon-intensive iron and steel sites is discussed. In this work, the logarithmic mean Divisia index (LMDI) method is used to decompose the changes in the energy consumption and CO2 emissions of iron and steel sites. The results show that the production scale significantly contributes to the increase in both energy consumption and CO2 emissions, with cumulative contributions of 229.63 and 255.36%, respectively. Energy recovery and credit emissions are two key factors decreasing site-level energy consumption and CO2 emissions, with cumulative contributions to the changes in energy consumption and CO2 emissions of -158.30 and -160.45%, respectively. A decrease in energy, flux, and carbon-containing material consumption per ton of steel promotes direct emission reduction, and purchased electricity savings greatly contribute to indirect emission reduction. In addition, site products and byproducts promote an increase in credit emissions and ultimately inhibit an increase in the total CO2 emissions of iron and steel sites.

Red mud recycling by Fe and Al recovery through the hydrometallurgy method: a collaborative strategy for aluminum and iron industry.

In this work, a collaborative strategy for the aluminum and iron industry based on red mud recycling through the hydrometallurgy method was proposed. In this method, Fe3+ and Al3+ were firstly separated from the red mud by using H2SO4 as a leaching agent, which was by-produced from the sintering process of an iron and steel industry. Multiple influence factors on the leaching process were investigated, with the H2SO4 addition amount showing the strongest influence on the leaching rates of Al and Fe. The main components of the filter residue were CaSO4, TiO2, and SiO2, which could be reused as additives in the building materials. Subsequently, the final Fe recovery product was obtained through the co-precipitation, Fe/Al separation, and Fe(OH)3 calcination. In the final product, the content of Fe2O3 reached 82.87%, and the iron grade was 58.01%, meeting the requirement being raw materials for sinter production.

Target the neglected VOCs emission from iron and steel industry in China for air quality improvement.

Recent years have witnessed significant improvement in China's air quality. Strict environmental protection measures have led to significant decreases in sulfur dioxide (SO2), nitrogen oxides (NO x ), and particulate matter (PM) emissions since 2013. But there is no denying that the air quality in 135 cities is inferior to reaching the Ambient Air Quality Standards (GB 3095-2012) in 2020. In terms of temporal, geographic, and historical aspects, we have analyzed the potential connections between China's air quality and the iron and steel industry. The non-target volatile organic compounds (VOCs) emissions from iron and steel industry, especially from the iron ore sinter process, may be an underappreciated index imposing a negative effect on the surrounding areas of China. Therefore, we appeal the authorities to pay more attention on VOCs emission from the iron and steel industry and establish new environmental standards. And different iron steel flue gas pollutants will be eliminated concurrently with the promotion and application of new technology.

The impact of financial development on CO2 emissions of global iron and steel industry.

As carbon peaking and carbon neutrality have become a global consensus, more and more countries have introduced relevant policies to adapt to their own countries and formulated corresponding time roadmap. The industrial sector, especially the steel sector, which produces high levels of pollution and carbon emissions, is facing significant pressure to transform its operations to reduce CO2 emissions. Previous studies have shown the importance of financial development (FD) in environmental protection; however, the impact of FD on the CO2 emissions of the steel sector is ignored. This paper examines the impact of FD on the CO2 emissions of the iron and steel industry from a global perspective using comprehensive panel data from a total of 30 countries during the period from 1990 to 2018. Empirical results show that an improved level of FD in a given country reduces the CO2 emissions of the iron and steel industry. The mechanism analysis indicates that FD promotes the upgrading of the structure of the iron and steel industry and the reduction of the CO2 emissions by means of the three-stage least square method. Our results also show that the effect of FD on reducing the CO2 emissions of the iron and steel industry in developing countries is less than its effect in developed countries. Estimation results also show the existence of the environmental Kuznets curve hypothesis in the iron and steel industry. Finally, we discuss the policy implications of achieving carbon neutrality in the steel sector.

[Pollution Characteristics and Emission Factors of PCDD/Fs from Iron and Steel Industry].

The pollution level, emission characteristics, and emission factors of PCDD/Fs from a number of steel plants were investigated in a particular province of China. The results showed that the concentration of PCDD/Fs was at a low level and decreased by 1-2 orders of magnitude compared with that in 2005-2019. In detail, the concentrations of PCDD/Fs ranged from 0.003-0.557 ng·m-3(I-TEQ), and the mean value was 0.165 ng·m-3 for the sintering process. Moreover, the concentrations of PCDD/Fs ranged from 0.006 to 0.057 ng·m-3, and the mean value was 0.025 ng·m-3 for the electric furnace process. In addition, the concentration of PCDD/Fs in the iron and steel industry from 2005 to 2020 increased first and then decreased, especially after the implementation of the new emission standard and the ultra-low emission control of conventional pollutants such as smoke, showing a significant decline. The results of fingerprint analysis showed that 2,3,7,8-TCDF was the largest congener contributing to the mass concentration, and lower chlorinated PCDFs were increased. This result differed from those of previous studies in which highly chlorinated PCDFs and PCDDs dominated, indicating that the generation source of PCDD/Fs had changed. The congener and isomer profiles of PCDD/Fs in flue gas from the sintering process were similar to those in the flue gas from the electric furnace process. Additionally, showing the characteristics of the typical high-temperature thermal process, the de novo synthesis may be the dominant mechanism of formation of PCDD/Fs in the sintering process and electric furnace process. The emission factor was 0.003-0.5 µg·t-1 (I-TEQ), and the average emission factor was (0.18±0.22) µg·t-1 for the sintering process. The emission factor was 0.04-0.5 µg·t-1, and the average emission factor was (0.27±0.23) µg·t-1 for the electric furnace process. These values were far lower than those of the standard toolkit for identification and quantification of dioxin and furan emissions released by UNEP in 2013 and the emission factors in the dioxin emission inventory of China in 2004. It is suggested that the emission factors of PCDD/Fs in the iron and steel industry of China should be studied and updated.